Chemiluminescent compositions, such as used in a basic “Glow-Stick” product, utilize a two-component system to chemically generate light. As with any contained chemical reaction, the reaction is limited in time, and once the components are mixed, the reaction will begin using up the reactive components. In chemiluminescent applications, the “glow” will begin bright, but will slowly fade as the reaction proceeds. In a typical two-component chemiluminescence system, the components are kept separate, where one is stored or sealed-off in a breakable container. When the user wishes to initiate the reaction (and create the “glow” effect), the user breaks the breakable container allowing mixing of the two components and thereby initiating the reaction.
In typical chemiluminescent applications the two components usually include (1) the “oxalate” component, and (2) the “activator” component, containing an oxidant, along with a fluorescer. When mixed the oxidant of the activator reacts with the oxalate to create highly reactive peroxy components that in turn act to excite the fluorescer, causing the glow effect. This two-component system is described in detail in U.S. Pat. Nos. 3,816,326, 4,313,843, 5,122,306, 7,674,406; and the United States patent application, Pub. No. 2010/0288984.
Traditional chemiluminescent oxidation compositions are in liquid form with very low viscosity (lower than 50 mPa·s); however, such low viscosity requires physical devices to store the components of the composition, even after the mixing, limiting the uses of such applications to contained applications, such as “glow sticks.” Further, the chemiluminescent effect and usage can be limited by the characteristics of containers.
Additionally, traditional chemiluminescent compounds require an oxidant, such as hydrogen peroxide, in relatively large concentrations. An oxidant is required as part of the activator component, and serves to react/activate the oxalate, creating the glow effect. However, use of such high concentrations of peroxide (which can have adverse affects such as bleaching of hair, skin and clothes) also necessitated that the compound be contained in a sealed container. Such a compound is fine for early popular uses, such as “glow sticks,” but was not suitable for a loose compound, such as a viscous gel or solid-state composition that could be used freely, and applied to the body or hair for example. U.S. Pat. No. 7,674,406 and United States patent application, Pub. No. 2010/0288984 overcome this problem by creating a viscous gel using lower oxidant concentrations, wherein the oxidant concentration is between 2% and 20%.
Chinese patent application 200610130440.4 and United States patent application, Pub. No. 2010/0288984 solve the problem by creating a solid-state chemiluminescent composition, in which the use of a container is optional after activation. It can be easily spread to a desired area for illumination or marking purpose. It is easy to remove, and will cause very little to no contamination. However, the product as disclosed by these applications exhibits particular shortcoming regarding stability that the present inventions seeks to address.
The solid-state compounds disclosed in the above prior art, and any known solid-state chemiluminescent compositions, are not only affected by the peroxide levels, but are also affected by the choice of solid filler used. The solid filler should have the following characteristics: (1) the solid should not affect the chemiluminescence reaction (i.e. the solid should not react with the other compounds); (2) the solid, within limit, must have a large enough surface area to weight ratio (low density); and (3) the solid should not have any, or at most a very low, adsorption property.
In all the prior art and known solid-state chemiluminescent compositions inorganic fillers are used, such as basic quartz sand. For instance, in United States patent application, Pub. No. 2010/0288984, the patent requires an “inorganic material,” see for example, paragraph 28, and both independent claims (claims 1 and 15) of the published application; the application particularly discusses use of inorganic oxides and salts, see for example, paragraphs 25 and 26 of the published application.
Although inorganic materials can be used for solid-state chemiluminescent composition and address some of the issues above—they are not ideal. Primarily because inorganics have possible reactivity issues and a density that is higher than desired. For instance: quartz sand, diatomaceous earth and kaolin are common inorganic materials used in such applications, and these (like all natural minerals) inevitably contain a variety of impurities, which may be reactive and could impact the chemiluminescence reaction, particularly if they contain, as is very common, impurities that are subject to oxidation, therefore prematurely reacting with the oxidant. Inorganics using silica, such as silica gel, have a strong adsorption property, which is undesirable for chemiluminescent reaction, since it reduces the amount of reactive chemicals available when the components are mixed, and thus negatively impacts the “glow” that is so desired in these products. In addition, all of these inorganic fillers have a relatively large density. The present invention seeks to address these shortcomings by using organic solids, which are less dense, exhibit lower adsorption properties, have little to no impurities, and are less reactive than the inorganic solids disclosed in the prior art.
Prior chemiluminescent solutions have enhanced stability by using a soluble organic polymer. Such as in U.S. Pat. No. 3,994,820 ('820), which discloses the use of polymer dissolved in the Oxalate component by heating the oxalate component to “80° C. for 5 to 10 minutes to effect complete solution of the polymers.” (See Table III of the '820 patent.) U.S. Pat. No. 5,824,242 ('242) discloses the use of a soluble organic polymer used at below 5% concentration by weight in solution, accompanied with a suspension of a partially soluble or insoluble red-dyed polymer used at concentration of 2-40% (see Col. 3, Ln. 9-14), that is used to enhance the “red” color glow effect created by a Rubrene containing compound. The stabilizing polymers in '820 and '242 are present at relatively low percentages, and are fully solubilized in solution, and the partially insoluble polymers of '242 are present to enhance the “red” color glow effect, and further are also at relatively low percentages, insubstantial to create a solid-state compound suitable for use as a glow-sand that can be freely used without the need for an external storage container.
Further, in the prior art and all known chemiluminescent products, the oxidizer is used at concentrations above 2% by mass. For example, U.S. Pat. No. 7,674,406 and United States patent application 2010/0288984, describe a chemiluminescent composition, with the use of an oxidizer at 2%-20%.
However oxidizers are, by definition, are reactive, and such products having higher peroxide concentrations have proven to have stability issues and exhibit a gassing problem. After packaging, such as while on a store shelf, bags containing such mixtures slowly fill with gas as oxidizing reactions occur. Such reactions impact the shelf life and efficacy of the product, and the gassing can cause pressure to build in a sealed container, thereby creating a potential harmful situation. Further, the bags will appear bloated on the shelf, which is likely to discourage consumers and create shelf space and storage issues at retail. In one embodiment of the present invention the mixture employs oxidizers below 2% concentration, thereby limiting the reactivity, decreasing gassing, and increasing the stability of the mixture. By using a low concentration of oxidizer and an organic solid, the present inventions solves the stability issues present in the prior art.